import React, { Component } from 'react'
import './index.css'

export default class Item extends Component {
  // 标识鼠标移入移出
  state = { mouse: false }

   
  handleMouse = (flag) => {
    return () => {
      this.setState({ mouse: flag })
    }
  }

  // 勾选，取消某一个todo回调
  handleCheck = (id) => {
    return (event) => {
      this.props.updateTodo(id,event.target.checked)
    }
  }

  // 删除一个todo回调 
  handleDelete = (id) => {
    if (window.confirm('确定删除吗？')) {
      this.props.deleteTodo(id)
    }
  }

  render() {
    const { id, name, done } = this.props
    const { mouse } = this.state
    return (
      <li style={{backgroundColor: mouse ? '#ddd' : 'white' }} onMouseEnter={this.handleMouse(true)} onMouseLeave={this.handleMouse(false)}>
        <label>
          <input type="checkbox" checked={done} onChange={this.handleCheck(id)}/>
          <span>{name}</span>
        </label>
        <button onClick={() => this.handleDelete(id)} className="btn btn-danger" style={{ display: mouse ? 'block' : 'none' }}>删除</button>
      </li>
    )
  }
}
